Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations, the description must carry the full behavioral burden. It does disclose the noteworthy cost and mechanism ('0.002 USDC per call via x402'), which is valuable, but says nothing about what a hit vs. clean result looks like, failure behavior, or whether payment is refunded on error.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Three tight sentences with the screening scope front-loaded, the trigger second, and cost last. No filler; every sentence earns its place.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a screening tool with no annotations and no output schema, the description covers invocation well but leaves the result contract undefined — an agent cannot tell what a positive/negative screen returns. That gap matters for a compliance check whose whole point is the verdict.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100%, and the schema itself documents both the address and the two-step paymentProof flow in detail. The description adds no parameter-level meaning beyond the schema, so the baseline 3 applies.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb+resource ('Screens a wallet address') against a named, authoritative list (US Treasury OFAC SDN) and enumerates the supported chains. It is immediately distinguishable from generic siblings like address_check or wallet_balance because the screening/OFAC intent is explicit.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

'Run before sending or accepting funds' gives a concrete trigger for invocation. It does not name an alternative or state when-not-to-use, so it falls short of the explicit routing a 5 requires.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.